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path: root/drivers/thermal/k3_j72xx_bandgap.c
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Diffstat (limited to 'drivers/thermal/k3_j72xx_bandgap.c')
-rw-r--r--drivers/thermal/k3_j72xx_bandgap.c565
1 files changed, 565 insertions, 0 deletions
diff --git a/drivers/thermal/k3_j72xx_bandgap.c b/drivers/thermal/k3_j72xx_bandgap.c
new file mode 100644
index 000000000..c073b1023
--- /dev/null
+++ b/drivers/thermal/k3_j72xx_bandgap.c
@@ -0,0 +1,565 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI Bandgap temperature sensor driver for J72XX SoC Family
+ *
+ * Copyright (C) 2021 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+#include <linux/math.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/pm_runtime.h>
+#include <linux/err.h>
+#include <linux/types.h>
+#include <linux/of_platform.h>
+#include <linux/io.h>
+#include <linux/thermal.h>
+#include <linux/of.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+
+#define K3_VTM_DEVINFO_PWR0_OFFSET 0x4
+#define K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK 0xf0
+#define K3_VTM_TMPSENS0_CTRL_OFFSET 0x300
+#define K3_VTM_MISC_CTRL_OFFSET 0xc
+#define K3_VTM_TMPSENS_STAT_OFFSET 0x8
+#define K3_VTM_ANYMAXT_OUTRG_ALERT_EN 0x1
+#define K3_VTM_MISC_CTRL2_OFFSET 0x10
+#define K3_VTM_TS_STAT_DTEMP_MASK 0x3ff
+#define K3_VTM_MAX_NUM_TS 8
+#define K3_VTM_TMPSENS_CTRL_SOC BIT(5)
+#define K3_VTM_TMPSENS_CTRL_CLRZ BIT(6)
+#define K3_VTM_TMPSENS_CTRL_CLKON_REQ BIT(7)
+#define K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN BIT(11)
+
+#define K3_VTM_CORRECTION_TEMP_CNT 3
+
+#define MINUS40CREF 5
+#define PLUS30CREF 253
+#define PLUS125CREF 730
+#define PLUS150CREF 940
+
+#define TABLE_SIZE 1024
+#define MAX_TEMP 123000
+#define COOL_DOWN_TEMP 105000
+
+#define FACTORS_REDUCTION 13
+static int *derived_table;
+
+static int compute_value(int index, const s64 *factors, int nr_factors,
+ int reduction)
+{
+ s64 value = 0;
+ int i;
+
+ for (i = 0; i < nr_factors; i++)
+ value += factors[i] * int_pow(index, i);
+
+ return (int)div64_s64(value, int_pow(10, reduction));
+}
+
+static void init_table(int factors_size, int *table, const s64 *factors)
+{
+ int i;
+
+ for (i = 0; i < TABLE_SIZE; i++)
+ table[i] = compute_value(i, factors, factors_size,
+ FACTORS_REDUCTION);
+}
+
+/**
+ * struct err_values - structure containing error/reference values
+ * @refs: reference error values for -40C, 30C, 125C & 150C
+ * @errs: Actual error values for -40C, 30C, 125C & 150C read from the efuse
+ */
+struct err_values {
+ int refs[4];
+ int errs[4];
+};
+
+static void create_table_segments(struct err_values *err_vals, int seg,
+ int *ref_table)
+{
+ int m = 0, c, num, den, i, err, idx1, idx2, err1, err2, ref1, ref2;
+
+ if (seg == 0)
+ idx1 = 0;
+ else
+ idx1 = err_vals->refs[seg];
+
+ idx2 = err_vals->refs[seg + 1];
+ err1 = err_vals->errs[seg];
+ err2 = err_vals->errs[seg + 1];
+ ref1 = err_vals->refs[seg];
+ ref2 = err_vals->refs[seg + 1];
+
+ /*
+ * Calculate the slope with adc values read from the register
+ * as the y-axis param and err in adc value as x-axis param
+ */
+ num = ref2 - ref1;
+ den = err2 - err1;
+ if (den)
+ m = num / den;
+ c = ref2 - m * err2;
+
+ /*
+ * Take care of divide by zero error if error values are same
+ * Or when the slope is 0
+ */
+ if (den != 0 && m != 0) {
+ for (i = idx1; i <= idx2; i++) {
+ err = (i - c) / m;
+ if (((i + err) < 0) || ((i + err) >= TABLE_SIZE))
+ continue;
+ derived_table[i] = ref_table[i + err];
+ }
+ } else { /* Constant error take care of divide by zero */
+ for (i = idx1; i <= idx2; i++) {
+ if (((i + err1) < 0) || ((i + err1) >= TABLE_SIZE))
+ continue;
+ derived_table[i] = ref_table[i + err1];
+ }
+ }
+}
+
+static int prep_lookup_table(struct err_values *err_vals, int *ref_table)
+{
+ int inc, i, seg;
+
+ /*
+ * Fill up the lookup table under 3 segments
+ * region -40C to +30C
+ * region +30C to +125C
+ * region +125C to +150C
+ */
+ for (seg = 0; seg < 3; seg++)
+ create_table_segments(err_vals, seg, ref_table);
+
+ /* Get to the first valid temperature */
+ i = 0;
+ while (!derived_table[i])
+ i++;
+
+ /*
+ * Get to the last zero index and back fill the temperature for
+ * sake of continuity
+ */
+ if (i) {
+ /* 300 milli celsius steps */
+ while (i--)
+ derived_table[i] = derived_table[i + 1] - 300;
+ }
+
+ /*
+ * Fill the last trailing 0s which are unfilled with increments of
+ * 100 milli celsius till 1023 code
+ */
+ i = TABLE_SIZE - 1;
+ while (!derived_table[i])
+ i--;
+
+ i++;
+ inc = 1;
+ while (i < TABLE_SIZE) {
+ derived_table[i] = derived_table[i - 1] + inc * 100;
+ i++;
+ }
+
+ return 0;
+}
+
+struct k3_thermal_data;
+
+struct k3_j72xx_bandgap {
+ struct device *dev;
+ void __iomem *base;
+ void __iomem *cfg2_base;
+ void __iomem *fuse_base;
+ struct k3_thermal_data *ts_data[K3_VTM_MAX_NUM_TS];
+};
+
+/* common data structures */
+struct k3_thermal_data {
+ struct k3_j72xx_bandgap *bgp;
+ u32 ctrl_offset;
+ u32 stat_offset;
+};
+
+static int two_cmp(int tmp, int mask)
+{
+ tmp = ~(tmp);
+ tmp &= mask;
+ tmp += 1;
+
+ /* Return negative value */
+ return (0 - tmp);
+}
+
+static unsigned int vtm_get_best_value(unsigned int s0, unsigned int s1,
+ unsigned int s2)
+{
+ int d01 = abs(s0 - s1);
+ int d02 = abs(s0 - s2);
+ int d12 = abs(s1 - s2);
+
+ if (d01 <= d02 && d01 <= d12)
+ return (s0 + s1) / 2;
+
+ if (d02 <= d01 && d02 <= d12)
+ return (s0 + s2) / 2;
+
+ return (s1 + s2) / 2;
+}
+
+static inline int k3_bgp_read_temp(struct k3_thermal_data *devdata,
+ int *temp)
+{
+ struct k3_j72xx_bandgap *bgp;
+ unsigned int dtemp, s0, s1, s2;
+
+ bgp = devdata->bgp;
+ /*
+ * Errata is applicable for am654 pg 1.0 silicon/J7ES. There
+ * is a variation of the order for certain degree centigrade on AM654.
+ * Work around that by getting the average of two closest
+ * readings out of three readings everytime we want to
+ * report temperatures.
+ *
+ * Errata workaround.
+ */
+ s0 = readl(bgp->base + devdata->stat_offset) &
+ K3_VTM_TS_STAT_DTEMP_MASK;
+ s1 = readl(bgp->base + devdata->stat_offset) &
+ K3_VTM_TS_STAT_DTEMP_MASK;
+ s2 = readl(bgp->base + devdata->stat_offset) &
+ K3_VTM_TS_STAT_DTEMP_MASK;
+ dtemp = vtm_get_best_value(s0, s1, s2);
+
+ if (dtemp < 0 || dtemp >= TABLE_SIZE)
+ return -EINVAL;
+
+ *temp = derived_table[dtemp];
+
+ return 0;
+}
+
+/* Get temperature callback function for thermal zone */
+static int k3_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
+{
+ struct k3_thermal_data *data = tz->devdata;
+ int ret = 0;
+
+ ret = k3_bgp_read_temp(data, temp);
+ if (ret)
+ return ret;
+
+ return ret;
+}
+
+static const struct thermal_zone_device_ops k3_of_thermal_ops = {
+ .get_temp = k3_thermal_get_temp,
+};
+
+static int k3_j72xx_bandgap_temp_to_adc_code(int temp)
+{
+ int low = 0, high = TABLE_SIZE - 1, mid;
+
+ if (temp > 160000 || temp < -50000)
+ return -EINVAL;
+
+ /* Binary search to find the adc code */
+ while (low < (high - 1)) {
+ mid = (low + high) / 2;
+ if (temp <= derived_table[mid])
+ high = mid;
+ else
+ low = mid;
+ }
+
+ return mid;
+}
+
+static void get_efuse_values(int id, struct k3_thermal_data *data, int *err,
+ struct k3_j72xx_bandgap *bgp)
+{
+ int i, tmp, pow;
+ int ct_offsets[5][K3_VTM_CORRECTION_TEMP_CNT] = {
+ { 0x0, 0x8, 0x4 },
+ { 0x0, 0x8, 0x4 },
+ { 0x0, -1, 0x4 },
+ { 0x0, 0xC, -1 },
+ { 0x0, 0xc, 0x8 }
+ };
+ int ct_bm[5][K3_VTM_CORRECTION_TEMP_CNT] = {
+ { 0x3f, 0x1fe000, 0x1ff },
+ { 0xfc0, 0x1fe000, 0x3fe00 },
+ { 0x3f000, 0x7f800000, 0x7fc0000 },
+ { 0xfc0000, 0x1fe0, 0x1f800000 },
+ { 0x3f000000, 0x1fe000, 0x1ff0 }
+ };
+
+ for (i = 0; i < 3; i++) {
+ /* Extract the offset value using bit-mask */
+ if (ct_offsets[id][i] == -1 && i == 1) {
+ /* 25C offset Case of Sensor 2 split between 2 regs */
+ tmp = (readl(bgp->fuse_base + 0x8) & 0xE0000000) >> (29);
+ tmp |= ((readl(bgp->fuse_base + 0xC) & 0x1F) << 3);
+ pow = tmp & 0x80;
+ } else if (ct_offsets[id][i] == -1 && i == 2) {
+ /* 125C Case of Sensor 3 split between 2 regs */
+ tmp = (readl(bgp->fuse_base + 0x4) & 0xF8000000) >> (27);
+ tmp |= ((readl(bgp->fuse_base + 0x8) & 0xF) << 5);
+ pow = tmp & 0x100;
+ } else {
+ tmp = readl(bgp->fuse_base + ct_offsets[id][i]);
+ tmp &= ct_bm[id][i];
+ tmp = tmp >> __ffs(ct_bm[id][i]);
+
+ /* Obtain the sign bit pow*/
+ pow = ct_bm[id][i] >> __ffs(ct_bm[id][i]);
+ pow += 1;
+ pow /= 2;
+ }
+
+ /* Check for negative value */
+ if (tmp & pow) {
+ /* 2's complement value */
+ tmp = two_cmp(tmp, ct_bm[id][i] >> __ffs(ct_bm[id][i]));
+ }
+ err[i] = tmp;
+ }
+
+ /* Err value for 150C is set to 0 */
+ err[i] = 0;
+}
+
+static void print_look_up_table(struct device *dev, int *ref_table)
+{
+ int i;
+
+ dev_dbg(dev, "The contents of derived array\n");
+ dev_dbg(dev, "Code Temperature\n");
+ for (i = 0; i < TABLE_SIZE; i++)
+ dev_dbg(dev, "%d %d %d\n", i, derived_table[i], ref_table[i]);
+}
+
+struct k3_j72xx_bandgap_data {
+ unsigned int has_errata_i2128;
+};
+
+static int k3_j72xx_bandgap_probe(struct platform_device *pdev)
+{
+ int ret = 0, cnt, val, id;
+ int high_max, low_temp;
+ struct resource *res;
+ struct device *dev = &pdev->dev;
+ struct k3_j72xx_bandgap *bgp;
+ struct k3_thermal_data *data;
+ int workaround_needed = 0;
+ const struct k3_j72xx_bandgap_data *driver_data;
+ struct thermal_zone_device *ti_thermal;
+ int *ref_table;
+ struct err_values err_vals;
+
+ const s64 golden_factors[] = {
+ -490019999999999936,
+ 3251200000000000,
+ -1705800000000,
+ 603730000,
+ -92627,
+ };
+
+ const s64 pvt_wa_factors[] = {
+ -415230000000000000,
+ 3126600000000000,
+ -1157800000000,
+ };
+
+ bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
+ if (!bgp)
+ return -ENOMEM;
+
+ bgp->dev = dev;
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ bgp->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(bgp->base))
+ return PTR_ERR(bgp->base);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ bgp->cfg2_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(bgp->cfg2_base))
+ return PTR_ERR(bgp->cfg2_base);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+ bgp->fuse_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(bgp->fuse_base))
+ return PTR_ERR(bgp->fuse_base);
+
+ driver_data = of_device_get_match_data(dev);
+ if (driver_data)
+ workaround_needed = driver_data->has_errata_i2128;
+
+ pm_runtime_enable(dev);
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(dev);
+ pm_runtime_disable(dev);
+ return ret;
+ }
+
+ /* Get the sensor count in the VTM */
+ val = readl(bgp->base + K3_VTM_DEVINFO_PWR0_OFFSET);
+ cnt = val & K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK;
+ cnt >>= __ffs(K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK);
+
+ data = devm_kcalloc(bgp->dev, cnt, sizeof(*data), GFP_KERNEL);
+ if (!data) {
+ ret = -ENOMEM;
+ goto err_alloc;
+ }
+
+ ref_table = kzalloc(sizeof(*ref_table) * TABLE_SIZE, GFP_KERNEL);
+ if (!ref_table) {
+ ret = -ENOMEM;
+ goto err_alloc;
+ }
+
+ derived_table = devm_kzalloc(bgp->dev, sizeof(*derived_table) * TABLE_SIZE,
+ GFP_KERNEL);
+ if (!derived_table) {
+ ret = -ENOMEM;
+ goto err_free_ref_table;
+ }
+
+ /* Workaround not needed if bit30/bit31 is set even for J721e */
+ if (workaround_needed && (readl(bgp->fuse_base + 0x0) & 0xc0000000) == 0xc0000000)
+ workaround_needed = false;
+
+ dev_dbg(bgp->dev, "Work around %sneeded\n",
+ workaround_needed ? "" : "not ");
+
+ if (!workaround_needed)
+ init_table(5, ref_table, golden_factors);
+ else
+ init_table(3, ref_table, pvt_wa_factors);
+
+ /* Register the thermal sensors */
+ for (id = 0; id < cnt; id++) {
+ data[id].bgp = bgp;
+ data[id].ctrl_offset = K3_VTM_TMPSENS0_CTRL_OFFSET + id * 0x20;
+ data[id].stat_offset = data[id].ctrl_offset +
+ K3_VTM_TMPSENS_STAT_OFFSET;
+
+ if (workaround_needed) {
+ /* ref adc values for -40C, 30C & 125C respectively */
+ err_vals.refs[0] = MINUS40CREF;
+ err_vals.refs[1] = PLUS30CREF;
+ err_vals.refs[2] = PLUS125CREF;
+ err_vals.refs[3] = PLUS150CREF;
+ get_efuse_values(id, &data[id], err_vals.errs, bgp);
+ }
+
+ if (id == 0 && workaround_needed)
+ prep_lookup_table(&err_vals, ref_table);
+ else if (id == 0 && !workaround_needed)
+ memcpy(derived_table, ref_table, TABLE_SIZE * 4);
+
+ val = readl(data[id].bgp->cfg2_base + data[id].ctrl_offset);
+ val |= (K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN |
+ K3_VTM_TMPSENS_CTRL_SOC |
+ K3_VTM_TMPSENS_CTRL_CLRZ | BIT(4));
+ writel(val, data[id].bgp->cfg2_base + data[id].ctrl_offset);
+
+ bgp->ts_data[id] = &data[id];
+ ti_thermal = devm_thermal_of_zone_register(bgp->dev, id, &data[id],
+ &k3_of_thermal_ops);
+ if (IS_ERR(ti_thermal)) {
+ dev_err(bgp->dev, "thermal zone device is NULL\n");
+ ret = PTR_ERR(ti_thermal);
+ goto err_free_ref_table;
+ }
+ }
+
+ /*
+ * Program TSHUT thresholds
+ * Step 1: set the thresholds to ~123C and 105C WKUP_VTM_MISC_CTRL2
+ * Step 2: WKUP_VTM_TMPSENS_CTRL_j set the MAXT_OUTRG_EN bit
+ * This is already taken care as per of init
+ * Step 3: WKUP_VTM_MISC_CTRL set the ANYMAXT_OUTRG_ALERT_EN bit
+ */
+ high_max = k3_j72xx_bandgap_temp_to_adc_code(MAX_TEMP);
+ low_temp = k3_j72xx_bandgap_temp_to_adc_code(COOL_DOWN_TEMP);
+
+ writel((low_temp << 16) | high_max, data[0].bgp->cfg2_base +
+ K3_VTM_MISC_CTRL2_OFFSET);
+ mdelay(100);
+ writel(K3_VTM_ANYMAXT_OUTRG_ALERT_EN, data[0].bgp->cfg2_base +
+ K3_VTM_MISC_CTRL_OFFSET);
+
+ platform_set_drvdata(pdev, bgp);
+
+ print_look_up_table(dev, ref_table);
+ /*
+ * Now that the derived_table has the appropriate look up values
+ * Free up the ref_table
+ */
+ kfree(ref_table);
+
+ return 0;
+
+err_free_ref_table:
+ kfree(ref_table);
+
+err_alloc:
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return ret;
+}
+
+static int k3_j72xx_bandgap_remove(struct platform_device *pdev)
+{
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+static const struct k3_j72xx_bandgap_data k3_j72xx_bandgap_j721e_data = {
+ .has_errata_i2128 = 1,
+};
+
+static const struct k3_j72xx_bandgap_data k3_j72xx_bandgap_j7200_data = {
+ .has_errata_i2128 = 0,
+};
+
+static const struct of_device_id of_k3_j72xx_bandgap_match[] = {
+ {
+ .compatible = "ti,j721e-vtm",
+ .data = &k3_j72xx_bandgap_j721e_data,
+ },
+ {
+ .compatible = "ti,j7200-vtm",
+ .data = &k3_j72xx_bandgap_j7200_data,
+ },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, of_k3_j72xx_bandgap_match);
+
+static struct platform_driver k3_j72xx_bandgap_sensor_driver = {
+ .probe = k3_j72xx_bandgap_probe,
+ .remove = k3_j72xx_bandgap_remove,
+ .driver = {
+ .name = "k3-j72xx-soc-thermal",
+ .of_match_table = of_k3_j72xx_bandgap_match,
+ },
+};
+
+module_platform_driver(k3_j72xx_bandgap_sensor_driver);
+
+MODULE_DESCRIPTION("K3 bandgap temperature sensor driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("J Keerthy <j-keerthy@ti.com>");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 21:11:41 +0000